When is Bolivia’s rainy season and how does rainfall differ by region?

Bolivia’s rainy season generally occurs from December to March, though the intensity and distribution of precipitation vary significantly across the country’s diverse geographic regions.1

• Highlands (Altiplano): Precipitation in the highlands varies greatly, and the region is often difficult to traverse during the rainy season. While the northern half of the Altiplano receives sufficient rainfall for crop cultivation, the southern half is characterized by a deficiency in moisture.123
• Yungas: This region experiences rainfall throughout the year, but it is heaviest between December and February, with annual totals reaching up to 53 inches (1,350 mm).1
• Oriente (Low Plains): These plains experience a pronounced summer maximum in rainfall. Annual totals range from approximately 40 inches (1,000 mm) in the south to 70 inches (1,800 mm) or more in the far north. Parts of the Beni department in this region are subject to extensive flooding toward the end of the summer rainy season, typically beginning in March or April.1
• Bolivian Chaco: This area is marked by striking seasonal changes; it transforms into a swamp during the rainy season but remains a hot semidesert for the majority of the year.4